Despite diesel engines being highly efficient, with low fuel consumption and reduced carbon dioxide emissions, they emit relatively high levels of particulate matter and oxides of nitrogen (NOx) due to high exhaust ga...Despite diesel engines being highly efficient, with low fuel consumption and reduced carbon dioxide emissions, they emit relatively high levels of particulate matter and oxides of nitrogen (NOx) due to high exhaust gas temperatures. Engine emissions show the quality and completeness of combustion. This paper aims to present the results of a study comparing exhaust emissions from a diesel and syngas powered engine. Syngas was produced from co-firing coal and biomass in a gasifier then cleaned, cooled and applied as an alternative fuel in an engine operated from 0 - 100% load. Exhaust-emissions were monitored at this load conditions. The exhaust-temperature was measured using thermocouples and the emission gases were analyzed using Testo 350. The emissions were lower and decreased as the engine load increased, except for sulphur dioxide and NOx. The study shows that levels of carbon monoxide, were higher in a range of 46.5 - 80.2%, while carbon dioxide was 3.3 - 18% higher compared to those from diesel. Hydrocarbon emissions were 480 and 1250 ppm for diesel and syngas respectively. The study reveals that the engine operates optimally at higher loads since hydrocarbons and oxides of carbon are low due to complete combustion at higher temperatures. Exhaust gas temperature was higher in the syngas fuel and increased as the engine load increased in the range of 455.83 - 480.03˚C which influenced the formation of NOx. NOx from diesel was found to be higher, ranging from 32.5 - 40.5%, compared to those from syngas with an engine load of 75%. The study observed that relative to diesel, the emissions of sulfur dioxide at 50% engine load were lower in a range of 23.7 - 57.1%. Emissions of hydrocarbons depended on the degree of substitution of diesel and engine load. The study therefore shows that, relative to diesel, emissions decreased when syngas was used with upgraded syngas from Prosporis juliflora presenting as the best alternative followed by Hyphanae compressa, and lastly rice husk. For optimal performance of the sy展开更多
Background: Obesity, especially central obesity, is a major risk factor for cardiovascular diseases and type-2 diabetes, known for their significant morbidity and mortality. University students are at increased risk o...Background: Obesity, especially central obesity, is a major risk factor for cardiovascular diseases and type-2 diabetes, known for their significant morbidity and mortality. University students are at increased risk of obesity due to adoption of unhealthy lifestyles and school-related stress. However, there is scant information regarding the prevalence and risk factors of obesity among university students in Kenya. The study aimed to determine the prevalence and factors associated with general and abdominal obesity among undergraduate students of The Catholic University of Eastern Africa, Kenya. Methods: A cross-sectional study design was employed among undergraduate students (n = 245) of The Catholic University of Eastern Africa, Nairobi. A systematic random sampling method was used to select the study participants. Lifestyle risk factors associated with obesity were collected using a structured questionnaire adopted from the WHO STEP-wise approach to non-communicable disease risk factor surveillance. Anthropometric measures of weight, height, and waist circumference were appropriately measured. The data were analyzed using SPSS software (ver: 22). The chi-square test of independence and binary logistic regression was used to establish an association between dependent and independent variables. Results: The prevalence of general and abdominal obesity was 19.6% and 27.8%, respectively. Risk factors of general obesity were age ≥ 20 years (OR, 9.95;95% CI, 3.09 - 32.08, p < 0.001), sedentary lifestyle (OR, 11.36;95% CI, 2.08 - 61.96, p = 0.005), staying with parents (OR, 3.22;95% CI, 1.09 - 9.58, p = 0.035), consumption of fast/processed foods (OR, 7.83;95% CI, 1.90 - 32.21, p = 0.004). Risk factors for abdominal obesity were being female (OR, 38.76;95% CI, 5.07 - 296.54, p < 0.001), staying with parents (OR, 3.02;95% CI, 1.14 - 7.99, p = 0.026) and sedentary lifestyle (OR, 6.55;95% CI, 1.80 - 23.81, p = 0.004). Conclusion: Being female, sedentary lifestyle, and consumption of fast/processed foods were found as p展开更多
Meteorological data is useful for varied applications and sectors ranging from weather and climate forecasting, landscape planning to disaster management among others. However, the availability of these data requires ...Meteorological data is useful for varied applications and sectors ranging from weather and climate forecasting, landscape planning to disaster management among others. However, the availability of these data requires a good network of manual meteorological stations and other support systems for its collection, recording, processing, archiving, communication and dissemination. In sub-Saharan Africa, such networks are limited due to low investment and capacity. To bridge this gap, the National Meteorological Services in Kenya and few others from African countries have moved to install a number of Automatic Weather Stations (AWSs) in the past decade including a few additions from private institutions and individuals. Although these AWSs have the potential to improve the existing observation network and the early warning systems in the region, the quality and capacity of the data collected from the stations are not well exploited. This is mainly due to low confidence, by data users, in electronically observed data. In this study, we set out to confirm that electronically observed data is of comparable quality to a human observer recorded data, and can thus be used to bridge data gaps at temporal and spatial scales. To assess this potential, we applied the simple Pearson correlation method and other statistical tests and approaches by conducting inter-comparison analysis of weather observations from the manual synoptic station and data from two Automatic Weather Stations (TAHMO and 3D-PAWS) co-located at KMD Headquarters to establish existing consistencies and variances in several weather parameters. Results show there is comparable consistency in most of the weather parameters between the three stations. Strong associations were noted between the TAHMO and manual station data for minimum (r = 0.65) and maximum temperatures (r = 0.86) and the maximum temperature between TAHMO and 3DPAWS (r = 0.56). Similar associations were indicated for surface pressure (r = 0.99) and RH (r > 0.6) with the weakest correlations occurr展开更多
Background: Preterm birth is a primary cause of neonatal morbidity and mortality especially in low-income countries. Although understanding the preventable factors of neonatal deaths in preterm infants is required for...Background: Preterm birth is a primary cause of neonatal morbidity and mortality especially in low-income countries. Although understanding the preventable factors of neonatal deaths in preterm infants is required for timely interventions, data on those factors is lacking in Kenya. We attempted to determine mortality and its associated factors in preterm babies in Kenya. Methods and Materials: A hospital-based, prospective study was implemented from July 2019 to October 2019 involving 163 preterm neonates and their mothers admitted at Kenyatta National Hospital. A systematic random sampling method was used to recruit the study participants. Data on mortality and the associated factors in preterm neonates were collected using a pretested questionnaire for mothers and neonatal medical records. Data was analyzed using descriptive and inferential statistics. Results: The mortality rate was 18.4%. Of the neonates who died, respiratory distress syndrome (63.3%) and neonatal sepsis (20.0%) were documented as the primary causes. Neonates born of single mother (AOR = 8.006, 95% CI 2.267 to 28.272, p = 0.001), unemployed (6.960, 1.059 - 45.757, p = 0.043), self-employed (4.040, 1.067 - 15.302, p = 0.040), anemic (7.465, 2.530 - 22.023, p < 0.001) and with history of bleeding during pregnancy were more likely to have died. The neonates born before 28 weeks of gestation (126.188, 14.554 - 1094.060, p < 0.001), those who did not cry immediately at birth (54.271, 5.970 - 493.395, p < 0.001) and the resuscitated at birth (54.406, 6.807 - 434.851, p < 0.001) were likely to die. Conclusion: High mortality rates of preterm neonates are attributed to both maternal and neonatal factors. Focused antenatal care should aim at early identification of high-risk mothers for early management of bleeding during pregnancy, close monitoring of nutritional status for mothers and health education.展开更多
<div style="text-align:justify;"> In the current study, we investigate the influence of proximate properties of five different fruits on voltage and current generated from a double chamber microbial fu...<div style="text-align:justify;"> In the current study, we investigate the influence of proximate properties of five different fruits on voltage and current generated from a double chamber microbial fuel cell. Fruits comprising of avocado, tomato, banana, watermelon and mango were analyzed for proximate properties using standard methods. Rumen fluid was used as the inoculum in fabricated H-shaped double chamber fuel cells with graphite rods electrodes at room temperature. The voltage and current generated were monitored daily for 30 days using a DT9205A digital multi-meter. The average moisture content for the fruits samples ranged from 82.86% - 95.16% while the crude fat was in the range of 0.12% - 0.33% with avocado having fat levels at 9.03%. Carbohydrates level was the highest in banana at 19.24% and the lowest in tomato waste at 2.93%. Tomato waste produced the highest voltage of 0.702 V on day 20 while lower voltage was noted in watermelon fruit wastes at 0.019 V. The voltage and current increased linearly with time for all the fruit wastes. These results indicate that substrate proximate properties influence the voltage and current generated in microbial fuel cell. In addition, moisture content and carbohydrates level were the major factors that influence microbial fuel cells performance. </div>展开更多
Rural communities in Kenya largely depend on plant resources for their livelihood.The utilization of these resources depends on the availability of plant resources and the level of knowledge of the residents.We conduc...Rural communities in Kenya largely depend on plant resources for their livelihood.The utilization of these resources depends on the availability of plant resources and the level of knowledge of the residents.We conducted an ethnobotanical study in Tharaka-Nithi County in Kenya to determine the knowledge and utilization of various plant species by the local communities.The study was conducted in four major administrative regions from June 2018 to February 2019,involving interview schedules using semi-structured open-ended questionnaires and guided field collections with 48 informants.A total of 214 plant species distributed in 73 families and 169 genera with 616 Use Reports(URs)were documented.Fabaceae was the highest family cited by the informants(31 species)followed by Lamiaceae and Euphorbiaceae(each with 11 species).Trees(49%)and shrubs(32%)were the top life forms of the plants frequently utilized by the local residents.The general plant uses reported were medicinal,food,fodder,construction,fuel,pesticidal,religious,live fencing,and making crafts.Zanthoxylum gilletii,Prunus africana,and Solanum incanum were found to be highly valued by the local communities.Plant utilization as food and medicinal uses against snake-bite related problems had the highest Informant Consensus Factor(ICF).Only 29(13.6%)of the species reported had their status assessed by the International Union for Conservation of Nature(IUCN).Conservation measures,alongside awareness creation in this region,are highly recommended for the species endemic to the region,highly depended on by the community,and those threatened according to IUCN standards.展开更多
Agricultural activities that encourage slashing, burning and ploughing greatly affect the soil structure and soil organic matter on which soil water retention depends. In this study, we hypothesized that inclusion of ...Agricultural activities that encourage slashing, burning and ploughing greatly affect the soil structure and soil organic matter on which soil water retention depends. In this study, we hypothesized that inclusion of rotational leguminous tree species improves soil water retention in a semi-arid conservation agriculture system. In a study done in Kibwezi, semi-arid eastern Kenya, results showed that the amount of water retained in the different soil strata from plots with different tree species and tillage practices was highly significant (P = 0.032). Plots with planting basins and Gliricidia sepium and Faidherbia albida tree species retained more water in both the upper and lower strata. Plots with G. sepium tree species under planting basins and zero tillage under F. albida had significantly higher soil organic carbon levels than plots that were managed under ridges and ploughing (P = 0.002). On the other hand, bulk density in plots with planting basins and zero tillage and ridges ranged between 1.35 g/cm3 and 1.53 g/cm3. Conventional tillage plots had bulk density values of 1.65 g/cm3 and 1.72 g/cm3 in the upper and lower strata respectively. The time-dependent nature of rotational leguminous tree species on soil organic matter and soil water retention in the semi-arid conservation agriculture system highlights the importance of considering these species for improving organic carbon and water retention for improved crop production.展开更多
This study was designed to use LiDAR data to research tree heights in montane forest blocks of Kenya. It uses a completely randomised block design to asses if differences exist in forest heights: 1) among montane fore...This study was designed to use LiDAR data to research tree heights in montane forest blocks of Kenya. It uses a completely randomised block design to asses if differences exist in forest heights: 1) among montane forest blocks, 2) among Agro ecological zones (AEZ) within each forest block and 3) between similar AEZ in different forest blocks. Forest height data from the Geoscience Laser Altimeter System (GLAS) on the Ice Cloud and Land Elevation Satellite (ICE-SAT) for the period 2003-2009 was used for 2146 circular plots, of 0.2 - 0.25 ha in size. Results indicate that, tree height is largely influenced by Agro ecological conditions and the wetter zones have taller trees in the upper, middle and lower highlands. In the upper highland zones of limited human activity, tree heights did not vary among forest blocks. Variations in height among forest blocks and within forest blocks were exaggerated in regions of active human intervention.展开更多
Transfer and transport of a passive scalar as well as flow structures of unbounded flow over a row of 2,3,4 and 5 equispaced identical cylinders at Re=90 and pitch ratios 1.05D≤S≤7D are investigated.Studies are perf...Transfer and transport of a passive scalar as well as flow structures of unbounded flow over a row of 2,3,4 and 5 equispaced identical cylinders at Re=90 and pitch ratios 1.05D≤S≤7D are investigated.Studies are performed through high fidelity simulations using a novel sharp-interface immersed boundary method.Five flow regimes are identified based on the nature of flow in the gap between the first two cylinders:dormant in the gap where fluid in the gap is motionless;symmetric in the gap where fluid in the gap behaves like a cavity flow;alternating in the gap where fluid in the gap is trapped but flaps up and down;wake in the gap where periodic vortices are shed in the gap;and bi-stable flow regime where vortices are shed in the gap for some time and then quasi-periodic twin vortices prevail for other times.A jump in values of hydrodynamic forces,pressure coefficient,Strouhal number,and Sherwood number is observed as pitch ratio increases due to change in flow structure.At high pitch ratio,a convectively unstable two-row vortical train is formed by the second cylinder.Member cylinders immersed in the two-row vortical structures have no effect on flow structure downstream or upstream and portray poor scalar transfer characteristics.The effect of configuration size on flow structures is found not to be as prominent as that of pitch ratio.展开更多
Although tea is grown in agro-ecological regions widely varying in environmental factors affecting yield and quality, planters usually import genetic materials across the different growing regions assuming genotypes w...Although tea is grown in agro-ecological regions widely varying in environmental factors affecting yield and quality, planters usually import genetic materials across the different growing regions assuming genotypes with good quality attributes in one location maintain their status in all regions. However, tea quality has not been replicated in new production regions. Black tea quality is influenced by the green leaf quality precursors including caffeine, total polyphenols and individual flavan-3-ols which are precursors of theaflavins and thearubigins, key plain black tea quality parameters. Factors influencing levels of the precursors compounds have not been quantified for popular Kenyan tea cultivars. The influence of geographical production location and seasons on levels and ratios of the quality precursors for 10 black tea popular clones grown in three locations in Kenya under uniform agronomic inputs were monitored. Caffeine varied significantly (P _〈 0.05) with clones and location but not with season. The flavan-3-ols and their ratios all varied (P 〈 0.05) with clones and site but not with season, with significant interactions (P 〈 0.05) between locations and clones, and locations and seasons. These results explain the observed variations in plain black tea quality due to clones and location of production. Thus, farmers in different locations are unlikely to produce black tea of same quality. It is therefore necessary to evaluate new tea genotypes in intended growing areas to establish cultivars suitable for producing high quality plain black teas in the locations. Seasonal variations in plain black tea in Kenya are unlikely to vary significantly due to flavan-3-ols.展开更多
Objective: This study compared the performance of the immunochromatographic strip (ICS) to the Venereal Disease Research Laboratory (VDRL) test and Treponema pallidum haemagglutination assay (TPHA) at a primary...Objective: This study compared the performance of the immunochromatographic strip (ICS) to the Venereal Disease Research Laboratory (VDRL) test and Treponema pallidum haemagglutination assay (TPHA) at a primary health care setting. Methods: The study group was comprised of 150 females randomly drawn from a population of pregnant women attending their first antenatal visit or follow-up visits at West Maternity Hospital in Eldoret Kenya, but without a previous syphilis test during that pregnancy. On-site VDRL, ICS and TPHA tests were performed and immediate treatment provided where appropriate. The performance of the three tests was compared, Results: The sero-prevalence of syphilis as determined by the VDRL test was 3%. There was no significant difference between the ICS and the VDRL test (P 〉 0.05). The sensitivity and specificity of the ICS test were 80% and 98.6% respectively, while the negative predictive value (NPV) and positive predictive value (PPV) were both 100%. On the other hand, the sensitivity and specificity of the VDRL test were 66.7% and 99.3%, while the NPV and PPV were 80% and 98.6% respectively. The Treponema pallidum haemagglutination assay was used as a reference test and had sensitivity, specificity, NPV and PPV of 100%. Conclusion: The diagnostic accuracy of the ICS compared favorably with theVDRL gold standard. The use of the ICS in Kenya can improve the diagnosis of syphilis in health facilities both with and without laboratories and allow community health care workers to make a rapid diagnosis of the disease, and consequently make immediate therapeutic decisions.展开更多
Taenia solium is an important food-bome pathogen worldwide and is emerging as a serious public health risk in both rural and urban communities where pigs are raised and consumed. Adult tapeworms are found in the intes...Taenia solium is an important food-bome pathogen worldwide and is emerging as a serious public health risk in both rural and urban communities where pigs are raised and consumed. Adult tapeworms are found in the intestines of humans while the developmental larval forms occur in the muscles and organs constituting cysticercosis of pigs and humans. Cysticercosis has a worldwide distribution, mainly related to poor hygiene and sanitation and consumption of infected pork. Pigs get infected through consumption of food and contaminated with human faeces containg eggs. In recent years pork consumption has increased with the opening up of pork eating centres. Porcine cysticercosis has previously been reported in Kenya, however, there are scarce data on the occurrence of the disease, as well as on the risk factors for transmission, in key production and consumption areas including Thika. The purpose of the study was to determine the seroprevalence of porcine cysticercosis in slaughtered pigs and associated risk factors for occurrence of the disease in selected abattoirs in Thika. Systematic random sampling was used to select a total of 276 pigs. The source of the slaughter pigs was derived fi'om the movement permits, the breed, sex and estimation of age was done at ante mortem examination. The slaughter and meat inspection processes were carried out by the slaughter house personnel and the investigators only observed and received the outcome of the inspection. Blood samples were collected fi'om each identified pig at slaughter, processed and analyzed using purified Taenia solium antigen ELISA commercial kit. The results meat inspection showed that none of the pigs in this study had any visible cysts whereas 4.35% of the pigs were seropositive which poses public health risk.展开更多
Road traffic accidents are a major cause of casualties and costly implications to all the stakeholders. Research focusing on the driver as one of the causal agent of accidents has been studied for centuries and with t...Road traffic accidents are a major cause of casualties and costly implications to all the stakeholders. Research focusing on the driver as one of the causal agent of accidents has been studied for centuries and with the advent of modernized driver assistance technologies. This paper sought to evaluate response of a driver using active-driving performance indicators like reaction time and physiological signal response (surface electromyogram), to understand hazard response behavior. Simulation of driving scenes was done using Unity3D engine and VR Head mounted display. The driver was presented with stimulus (collision objects) of different size and distance. From the results, an event scene that the driver considered hazardous was marked with increased electromyography response distinct from non-event scenes. From the results, we noted an increase in pedal misapplication during hazard response. The proposed approach is applicable in a real time driving analysis for on-road risk level classification.展开更多
In this paper, an autonomous and distributive demand-side management based on Bayesian game theory is developed and applied among users in a grid connected micro-grid with storage. To derive that strategy, an energy c...In this paper, an autonomous and distributive demand-side management based on Bayesian game theory is developed and applied among users in a grid connected micro-grid with storage. To derive that strategy, an energy consumption of shiftable loads belonging to a given user is modelled as a noncooperative three-player game of incomplete information, in which each user plays against the storage unit and an opponent gathering all the other users in the micro-grid. Each player is assumed to be endowed with statistical information about its behavior and that of its opponents so that he can take actions maximizing his expected utility. Results of the proposed strategy evaluated by simulating, under MATLAB environment, a connected micro-grid with storage device evidence its efficacy when employed to manage the charging of electric vehicles.展开更多
Background:Long-lasting insecticide nets(LLINs)are a core malaria intervention.LLINs should retain efficacy against mosquito vectors for a minimum of three years.Efficacy and durability of Olyset®Plus,a permethri...Background:Long-lasting insecticide nets(LLINs)are a core malaria intervention.LLINs should retain efficacy against mosquito vectors for a minimum of three years.Efficacy and durability of Olyset®Plus,a permethrin and piperonyl butoxide(PBO)treated LLIN,was evaluated versus permethrin treated Olyset®Net.In the absence of WHO guidelines of how to evaluate PBO nets,and considering the manufacturer’s product claim,Olyset®Plus was evaluated as a pyrethroid LLIN.Methods:This was a household randomized controlled trial in a malaria endemic rice cultivation zone of Kirinyaga County,Kenya between 2014 and 2017.Cone bioassays and tunnel tests were done against Anopheles gambiae Kisumu.The chemical content,fabric integrity and LLIN survivorship were monitored.Comparisons between nets were tested for signifcance using the Chi-square test.Exact binomial distribution with 95%confdence intervals(95%CI)was used for percentages.The WHO efcacy criteria used were≥95%knockdown and/or≥80%mortality rate in cone bioassays and≥80%mortality and/or≥90%blood-feeding inhibition in tunnel tests.Results:At 36 months,Olyset®Plus lost 52%permethrin and 87%PBO content;Olyset®Net lost 24%permethrin.Over 80%of Olyset®Plus and Olyset®Net passed the WHO efcacy criteria for LLINs up to 18 and 12 months,respec‑tively.At month 36,91.2%Olyset®Plus and 86.4%Olyset®Net survived,while 72%and 63%developed at least one hole.The proportionate Hole Index(pHI)values representing nets in good,serviceable and torn condition were 49.6%,27.1%and 23.2%,respectively for Olyset®Plus,and 44.9%,32.8%and 22.2%,respectively for Olyset®Net but were not signifcantly diferent.Conclusions:Olyset®Plus retained efcacy above or close to the WHO efcacy criteria for about 2 years than Olyset®Net(1–1.5 years).Both nets did not meet the 3-year WHO efcacy criteria,and showed little attrition,comparable physical durability and survivorship,with 50%of Olyset®Plus having good and serviceable condition after 3 years.Better community education on appropriate u展开更多
Inorganic fertilizer NPK (nitrogen, phosphorus and potassium) (S) 25:5:5:5 is generally recommended for optimum yield and quality of tea (Camellia sinensis). Non-judicious use of this inorganic fertilizer how...Inorganic fertilizer NPK (nitrogen, phosphorus and potassium) (S) 25:5:5:5 is generally recommended for optimum yield and quality of tea (Camellia sinensis). Non-judicious use of this inorganic fertilizer however acidifies the soils and pollutes the environment. Integrated soil fertility management (ISFM) which involves the combined use of organic and inorganic fertilizer is recommended for improved crop yield and soil health. An experiment was carried out to determine the effect of enriching cattle manure with different ratios of inorganic fertilizers (OM: NPKS at ratios 1:2 and 1:4), and rates on soil nutrient status, nitrogen uptake and yield of tea in the east of Rift Valley, Kenya. Enriching manures and organic manure up to a rate of 150 kg N/ha increased the level of P mature leaf. A higher N and K level in the mature leaf was observed when NPKS was applied at higher rates. In the soil, fertilizer rate up to 150 kg N/ha showed higher pH and K where organic manure and enriched manures were applied while NPKS treatment showed higher P content throughout the soil depths. Enriching organic manures with inorganic fertilizers increased yield significantly.展开更多
The paper analyzes the relationship between remittances and financial development using Kenyan quarterly data from 2006 to 2016.Five different indicators of financial development are used:credit to the private sector ...The paper analyzes the relationship between remittances and financial development using Kenyan quarterly data from 2006 to 2016.Five different indicators of financial development are used:credit to the private sector as a share of GDP,the number of mobile transactions,the value of these mobile transactions,the number of mobile agents,and the number of bank accounts.The results from using an autoregressive distributed lag demonstrate a strong,positive relationship between remittances and financial development in long-run equations.This suggests that higher levels of remittances provide opportunities for recipients to open bank accounts,enhance their savings,and access financial systems,in addition to exposing the previously unbanked to both new and existing financial products.The results also confirm the potential advantage of embracing modern and advanced technology to facilitate international mobile transfers.Using international remittance transfers through mobile technology reduces costs by eliminating the need for physical branches and personnel to attend to walk-in customers.Aside from offering convenience and safety for remittance actors,this method also dominates traditional remittance business models.Therefore,a policy window exists for the government to leverage on remittances as a tool of financial inclusion and depth,and particularly through the continued expansion of regulatory space to accommodate the wider use of international mobile remittance transfer channels.Moreover,given the strong,positive relationship between remittances and credit to the private sector as indicated by its share of GDP and number of bank accounts,commercial banks and other players in the remittance market may also find it useful to develop customized products for migrants to access their remittances.For example,financial intermediaries can consider providing better deposit interest rates for diaspora deposits compared to deposits made in the local currency.Further,these institutions can allow regular remittance flows to act a展开更多
Busia and Kisii Central districts are areas in western Kenya that have repeatedly reported high levels of stunting growth in children and an increase in hepatocellular carcinoma (HCC);an aspect often positively associ...Busia and Kisii Central districts are areas in western Kenya that have repeatedly reported high levels of stunting growth in children and an increase in hepatocellular carcinoma (HCC);an aspect often positively associated with chronic exposure to aflatoxins especially through consumption of foods such as peanuts. The objectives of the study were to determine the incidence, types and levels of aflatoxin in different varieties of peanuts produced in Busia and Kisii Central districts. One hundred and two (102) peanuts samples were collected from farmers’ in each district. Aflatoxin types and levels of aflatoxins were analyzed using high performance liquid chromatography (HPLC) technique. All the peanuts samples from Kisii Central and 97.06% samples from Busia were contaminated with aflatoxins. However, aflatoxin was not detected in 2.94% of samples from Busia district. The levels of total aflatoxin ranges were 0.1 to 268 μg/kg and 1.63 to 591.1 μg/kg in peanuts from Busia and Kisii Central respectively. Majority of peanuts samples had levels within Kenya Bureau of Standards (KEBS) and European Union (EU) regulatory limits for total aflatoxins. Improved variety (Valencia red) had significantly lower aflatoxin contamination compared to local varieties (Uganda local red, Homabay local and Local red). Aflatoxins B1, B2, G1 and G2 were found in peanuts;B1 was the most predominant in both districts (t = 12.4, df = 3, P = 0.034). The levels of aflatoxins especially in peanuts from Kisii Central district were high (591.1 μg/kg) where 44.6% of samples analyzed were unfit for even animal feed (USFDA regulatory limit). An assessment on the levels of aflatoxins should be done by the relevant stakeholders in other key foods in the areas for example maize. The most lethal aflatoxin type B1 was found to be the most predominant peanuts from both districts of study. This calls for frequent aflatoxin screening of peanuts from the districts particularly aflatoxin type B.展开更多
文摘Despite diesel engines being highly efficient, with low fuel consumption and reduced carbon dioxide emissions, they emit relatively high levels of particulate matter and oxides of nitrogen (NOx) due to high exhaust gas temperatures. Engine emissions show the quality and completeness of combustion. This paper aims to present the results of a study comparing exhaust emissions from a diesel and syngas powered engine. Syngas was produced from co-firing coal and biomass in a gasifier then cleaned, cooled and applied as an alternative fuel in an engine operated from 0 - 100% load. Exhaust-emissions were monitored at this load conditions. The exhaust-temperature was measured using thermocouples and the emission gases were analyzed using Testo 350. The emissions were lower and decreased as the engine load increased, except for sulphur dioxide and NOx. The study shows that levels of carbon monoxide, were higher in a range of 46.5 - 80.2%, while carbon dioxide was 3.3 - 18% higher compared to those from diesel. Hydrocarbon emissions were 480 and 1250 ppm for diesel and syngas respectively. The study reveals that the engine operates optimally at higher loads since hydrocarbons and oxides of carbon are low due to complete combustion at higher temperatures. Exhaust gas temperature was higher in the syngas fuel and increased as the engine load increased in the range of 455.83 - 480.03˚C which influenced the formation of NOx. NOx from diesel was found to be higher, ranging from 32.5 - 40.5%, compared to those from syngas with an engine load of 75%. The study observed that relative to diesel, the emissions of sulfur dioxide at 50% engine load were lower in a range of 23.7 - 57.1%. Emissions of hydrocarbons depended on the degree of substitution of diesel and engine load. The study therefore shows that, relative to diesel, emissions decreased when syngas was used with upgraded syngas from Prosporis juliflora presenting as the best alternative followed by Hyphanae compressa, and lastly rice husk. For optimal performance of the sy
文摘Background: Obesity, especially central obesity, is a major risk factor for cardiovascular diseases and type-2 diabetes, known for their significant morbidity and mortality. University students are at increased risk of obesity due to adoption of unhealthy lifestyles and school-related stress. However, there is scant information regarding the prevalence and risk factors of obesity among university students in Kenya. The study aimed to determine the prevalence and factors associated with general and abdominal obesity among undergraduate students of The Catholic University of Eastern Africa, Kenya. Methods: A cross-sectional study design was employed among undergraduate students (n = 245) of The Catholic University of Eastern Africa, Nairobi. A systematic random sampling method was used to select the study participants. Lifestyle risk factors associated with obesity were collected using a structured questionnaire adopted from the WHO STEP-wise approach to non-communicable disease risk factor surveillance. Anthropometric measures of weight, height, and waist circumference were appropriately measured. The data were analyzed using SPSS software (ver: 22). The chi-square test of independence and binary logistic regression was used to establish an association between dependent and independent variables. Results: The prevalence of general and abdominal obesity was 19.6% and 27.8%, respectively. Risk factors of general obesity were age ≥ 20 years (OR, 9.95;95% CI, 3.09 - 32.08, p < 0.001), sedentary lifestyle (OR, 11.36;95% CI, 2.08 - 61.96, p = 0.005), staying with parents (OR, 3.22;95% CI, 1.09 - 9.58, p = 0.035), consumption of fast/processed foods (OR, 7.83;95% CI, 1.90 - 32.21, p = 0.004). Risk factors for abdominal obesity were being female (OR, 38.76;95% CI, 5.07 - 296.54, p < 0.001), staying with parents (OR, 3.02;95% CI, 1.14 - 7.99, p = 0.026) and sedentary lifestyle (OR, 6.55;95% CI, 1.80 - 23.81, p = 0.004). Conclusion: Being female, sedentary lifestyle, and consumption of fast/processed foods were found as p
文摘Meteorological data is useful for varied applications and sectors ranging from weather and climate forecasting, landscape planning to disaster management among others. However, the availability of these data requires a good network of manual meteorological stations and other support systems for its collection, recording, processing, archiving, communication and dissemination. In sub-Saharan Africa, such networks are limited due to low investment and capacity. To bridge this gap, the National Meteorological Services in Kenya and few others from African countries have moved to install a number of Automatic Weather Stations (AWSs) in the past decade including a few additions from private institutions and individuals. Although these AWSs have the potential to improve the existing observation network and the early warning systems in the region, the quality and capacity of the data collected from the stations are not well exploited. This is mainly due to low confidence, by data users, in electronically observed data. In this study, we set out to confirm that electronically observed data is of comparable quality to a human observer recorded data, and can thus be used to bridge data gaps at temporal and spatial scales. To assess this potential, we applied the simple Pearson correlation method and other statistical tests and approaches by conducting inter-comparison analysis of weather observations from the manual synoptic station and data from two Automatic Weather Stations (TAHMO and 3D-PAWS) co-located at KMD Headquarters to establish existing consistencies and variances in several weather parameters. Results show there is comparable consistency in most of the weather parameters between the three stations. Strong associations were noted between the TAHMO and manual station data for minimum (r = 0.65) and maximum temperatures (r = 0.86) and the maximum temperature between TAHMO and 3DPAWS (r = 0.56). Similar associations were indicated for surface pressure (r = 0.99) and RH (r > 0.6) with the weakest correlations occurr
文摘Background: Preterm birth is a primary cause of neonatal morbidity and mortality especially in low-income countries. Although understanding the preventable factors of neonatal deaths in preterm infants is required for timely interventions, data on those factors is lacking in Kenya. We attempted to determine mortality and its associated factors in preterm babies in Kenya. Methods and Materials: A hospital-based, prospective study was implemented from July 2019 to October 2019 involving 163 preterm neonates and their mothers admitted at Kenyatta National Hospital. A systematic random sampling method was used to recruit the study participants. Data on mortality and the associated factors in preterm neonates were collected using a pretested questionnaire for mothers and neonatal medical records. Data was analyzed using descriptive and inferential statistics. Results: The mortality rate was 18.4%. Of the neonates who died, respiratory distress syndrome (63.3%) and neonatal sepsis (20.0%) were documented as the primary causes. Neonates born of single mother (AOR = 8.006, 95% CI 2.267 to 28.272, p = 0.001), unemployed (6.960, 1.059 - 45.757, p = 0.043), self-employed (4.040, 1.067 - 15.302, p = 0.040), anemic (7.465, 2.530 - 22.023, p < 0.001) and with history of bleeding during pregnancy were more likely to have died. The neonates born before 28 weeks of gestation (126.188, 14.554 - 1094.060, p < 0.001), those who did not cry immediately at birth (54.271, 5.970 - 493.395, p < 0.001) and the resuscitated at birth (54.406, 6.807 - 434.851, p < 0.001) were likely to die. Conclusion: High mortality rates of preterm neonates are attributed to both maternal and neonatal factors. Focused antenatal care should aim at early identification of high-risk mothers for early management of bleeding during pregnancy, close monitoring of nutritional status for mothers and health education.
文摘<div style="text-align:justify;"> In the current study, we investigate the influence of proximate properties of five different fruits on voltage and current generated from a double chamber microbial fuel cell. Fruits comprising of avocado, tomato, banana, watermelon and mango were analyzed for proximate properties using standard methods. Rumen fluid was used as the inoculum in fabricated H-shaped double chamber fuel cells with graphite rods electrodes at room temperature. The voltage and current generated were monitored daily for 30 days using a DT9205A digital multi-meter. The average moisture content for the fruits samples ranged from 82.86% - 95.16% while the crude fat was in the range of 0.12% - 0.33% with avocado having fat levels at 9.03%. Carbohydrates level was the highest in banana at 19.24% and the lowest in tomato waste at 2.93%. Tomato waste produced the highest voltage of 0.702 V on day 20 while lower voltage was noted in watermelon fruit wastes at 0.019 V. The voltage and current increased linearly with time for all the fruit wastes. These results indicate that substrate proximate properties influence the voltage and current generated in microbial fuel cell. In addition, moisture content and carbohydrates level were the major factors that influence microbial fuel cells performance. </div>
基金We acknowledge the support of the foresters,rangers,area chiefs,sub-chiefs and residents of Tharaka-Nithi county accorded to this study.The Kenya Forest Service for the fieldwork permits and the scientist Mr.Ken Wambua of National Museums of Kenya for help with specimen identification.Dr.Emily Wabuyele who gave helpful insights in the development of this manuscript.This research was supported by grants of the National Natural Science Foundation of China(31970211)from the Sino-Africa Joint Research Centre,CAS(SAJC201614).
文摘Rural communities in Kenya largely depend on plant resources for their livelihood.The utilization of these resources depends on the availability of plant resources and the level of knowledge of the residents.We conducted an ethnobotanical study in Tharaka-Nithi County in Kenya to determine the knowledge and utilization of various plant species by the local communities.The study was conducted in four major administrative regions from June 2018 to February 2019,involving interview schedules using semi-structured open-ended questionnaires and guided field collections with 48 informants.A total of 214 plant species distributed in 73 families and 169 genera with 616 Use Reports(URs)were documented.Fabaceae was the highest family cited by the informants(31 species)followed by Lamiaceae and Euphorbiaceae(each with 11 species).Trees(49%)and shrubs(32%)were the top life forms of the plants frequently utilized by the local residents.The general plant uses reported were medicinal,food,fodder,construction,fuel,pesticidal,religious,live fencing,and making crafts.Zanthoxylum gilletii,Prunus africana,and Solanum incanum were found to be highly valued by the local communities.Plant utilization as food and medicinal uses against snake-bite related problems had the highest Informant Consensus Factor(ICF).Only 29(13.6%)of the species reported had their status assessed by the International Union for Conservation of Nature(IUCN).Conservation measures,alongside awareness creation in this region,are highly recommended for the species endemic to the region,highly depended on by the community,and those threatened according to IUCN standards.
文摘Agricultural activities that encourage slashing, burning and ploughing greatly affect the soil structure and soil organic matter on which soil water retention depends. In this study, we hypothesized that inclusion of rotational leguminous tree species improves soil water retention in a semi-arid conservation agriculture system. In a study done in Kibwezi, semi-arid eastern Kenya, results showed that the amount of water retained in the different soil strata from plots with different tree species and tillage practices was highly significant (P = 0.032). Plots with planting basins and Gliricidia sepium and Faidherbia albida tree species retained more water in both the upper and lower strata. Plots with G. sepium tree species under planting basins and zero tillage under F. albida had significantly higher soil organic carbon levels than plots that were managed under ridges and ploughing (P = 0.002). On the other hand, bulk density in plots with planting basins and zero tillage and ridges ranged between 1.35 g/cm3 and 1.53 g/cm3. Conventional tillage plots had bulk density values of 1.65 g/cm3 and 1.72 g/cm3 in the upper and lower strata respectively. The time-dependent nature of rotational leguminous tree species on soil organic matter and soil water retention in the semi-arid conservation agriculture system highlights the importance of considering these species for improving organic carbon and water retention for improved crop production.
文摘This study was designed to use LiDAR data to research tree heights in montane forest blocks of Kenya. It uses a completely randomised block design to asses if differences exist in forest heights: 1) among montane forest blocks, 2) among Agro ecological zones (AEZ) within each forest block and 3) between similar AEZ in different forest blocks. Forest height data from the Geoscience Laser Altimeter System (GLAS) on the Ice Cloud and Land Elevation Satellite (ICE-SAT) for the period 2003-2009 was used for 2146 circular plots, of 0.2 - 0.25 ha in size. Results indicate that, tree height is largely influenced by Agro ecological conditions and the wetter zones have taller trees in the upper, middle and lower highlands. In the upper highland zones of limited human activity, tree heights did not vary among forest blocks. Variations in height among forest blocks and within forest blocks were exaggerated in regions of active human intervention.
文摘Transfer and transport of a passive scalar as well as flow structures of unbounded flow over a row of 2,3,4 and 5 equispaced identical cylinders at Re=90 and pitch ratios 1.05D≤S≤7D are investigated.Studies are performed through high fidelity simulations using a novel sharp-interface immersed boundary method.Five flow regimes are identified based on the nature of flow in the gap between the first two cylinders:dormant in the gap where fluid in the gap is motionless;symmetric in the gap where fluid in the gap behaves like a cavity flow;alternating in the gap where fluid in the gap is trapped but flaps up and down;wake in the gap where periodic vortices are shed in the gap;and bi-stable flow regime where vortices are shed in the gap for some time and then quasi-periodic twin vortices prevail for other times.A jump in values of hydrodynamic forces,pressure coefficient,Strouhal number,and Sherwood number is observed as pitch ratio increases due to change in flow structure.At high pitch ratio,a convectively unstable two-row vortical train is formed by the second cylinder.Member cylinders immersed in the two-row vortical structures have no effect on flow structure downstream or upstream and portray poor scalar transfer characteristics.The effect of configuration size on flow structures is found not to be as prominent as that of pitch ratio.
文摘Although tea is grown in agro-ecological regions widely varying in environmental factors affecting yield and quality, planters usually import genetic materials across the different growing regions assuming genotypes with good quality attributes in one location maintain their status in all regions. However, tea quality has not been replicated in new production regions. Black tea quality is influenced by the green leaf quality precursors including caffeine, total polyphenols and individual flavan-3-ols which are precursors of theaflavins and thearubigins, key plain black tea quality parameters. Factors influencing levels of the precursors compounds have not been quantified for popular Kenyan tea cultivars. The influence of geographical production location and seasons on levels and ratios of the quality precursors for 10 black tea popular clones grown in three locations in Kenya under uniform agronomic inputs were monitored. Caffeine varied significantly (P _〈 0.05) with clones and location but not with season. The flavan-3-ols and their ratios all varied (P 〈 0.05) with clones and site but not with season, with significant interactions (P 〈 0.05) between locations and clones, and locations and seasons. These results explain the observed variations in plain black tea quality due to clones and location of production. Thus, farmers in different locations are unlikely to produce black tea of same quality. It is therefore necessary to evaluate new tea genotypes in intended growing areas to establish cultivars suitable for producing high quality plain black teas in the locations. Seasonal variations in plain black tea in Kenya are unlikely to vary significantly due to flavan-3-ols.
文摘Objective: This study compared the performance of the immunochromatographic strip (ICS) to the Venereal Disease Research Laboratory (VDRL) test and Treponema pallidum haemagglutination assay (TPHA) at a primary health care setting. Methods: The study group was comprised of 150 females randomly drawn from a population of pregnant women attending their first antenatal visit or follow-up visits at West Maternity Hospital in Eldoret Kenya, but without a previous syphilis test during that pregnancy. On-site VDRL, ICS and TPHA tests were performed and immediate treatment provided where appropriate. The performance of the three tests was compared, Results: The sero-prevalence of syphilis as determined by the VDRL test was 3%. There was no significant difference between the ICS and the VDRL test (P 〉 0.05). The sensitivity and specificity of the ICS test were 80% and 98.6% respectively, while the negative predictive value (NPV) and positive predictive value (PPV) were both 100%. On the other hand, the sensitivity and specificity of the VDRL test were 66.7% and 99.3%, while the NPV and PPV were 80% and 98.6% respectively. The Treponema pallidum haemagglutination assay was used as a reference test and had sensitivity, specificity, NPV and PPV of 100%. Conclusion: The diagnostic accuracy of the ICS compared favorably with theVDRL gold standard. The use of the ICS in Kenya can improve the diagnosis of syphilis in health facilities both with and without laboratories and allow community health care workers to make a rapid diagnosis of the disease, and consequently make immediate therapeutic decisions.
文摘Taenia solium is an important food-bome pathogen worldwide and is emerging as a serious public health risk in both rural and urban communities where pigs are raised and consumed. Adult tapeworms are found in the intestines of humans while the developmental larval forms occur in the muscles and organs constituting cysticercosis of pigs and humans. Cysticercosis has a worldwide distribution, mainly related to poor hygiene and sanitation and consumption of infected pork. Pigs get infected through consumption of food and contaminated with human faeces containg eggs. In recent years pork consumption has increased with the opening up of pork eating centres. Porcine cysticercosis has previously been reported in Kenya, however, there are scarce data on the occurrence of the disease, as well as on the risk factors for transmission, in key production and consumption areas including Thika. The purpose of the study was to determine the seroprevalence of porcine cysticercosis in slaughtered pigs and associated risk factors for occurrence of the disease in selected abattoirs in Thika. Systematic random sampling was used to select a total of 276 pigs. The source of the slaughter pigs was derived fi'om the movement permits, the breed, sex and estimation of age was done at ante mortem examination. The slaughter and meat inspection processes were carried out by the slaughter house personnel and the investigators only observed and received the outcome of the inspection. Blood samples were collected fi'om each identified pig at slaughter, processed and analyzed using purified Taenia solium antigen ELISA commercial kit. The results meat inspection showed that none of the pigs in this study had any visible cysts whereas 4.35% of the pigs were seropositive which poses public health risk.
文摘Road traffic accidents are a major cause of casualties and costly implications to all the stakeholders. Research focusing on the driver as one of the causal agent of accidents has been studied for centuries and with the advent of modernized driver assistance technologies. This paper sought to evaluate response of a driver using active-driving performance indicators like reaction time and physiological signal response (surface electromyogram), to understand hazard response behavior. Simulation of driving scenes was done using Unity3D engine and VR Head mounted display. The driver was presented with stimulus (collision objects) of different size and distance. From the results, an event scene that the driver considered hazardous was marked with increased electromyography response distinct from non-event scenes. From the results, we noted an increase in pedal misapplication during hazard response. The proposed approach is applicable in a real time driving analysis for on-road risk level classification.
文摘In this paper, an autonomous and distributive demand-side management based on Bayesian game theory is developed and applied among users in a grid connected micro-grid with storage. To derive that strategy, an energy consumption of shiftable loads belonging to a given user is modelled as a noncooperative three-player game of incomplete information, in which each user plays against the storage unit and an opponent gathering all the other users in the micro-grid. Each player is assumed to be endowed with statistical information about its behavior and that of its opponents so that he can take actions maximizing his expected utility. Results of the proposed strategy evaluated by simulating, under MATLAB environment, a connected micro-grid with storage device evidence its efficacy when employed to manage the charging of electric vehicles.
基金The work was funded as a collaborative project by the WHO Pesticide Evalua‑tion Scheme,Geneva,Switzerland.
文摘Background:Long-lasting insecticide nets(LLINs)are a core malaria intervention.LLINs should retain efficacy against mosquito vectors for a minimum of three years.Efficacy and durability of Olyset®Plus,a permethrin and piperonyl butoxide(PBO)treated LLIN,was evaluated versus permethrin treated Olyset®Net.In the absence of WHO guidelines of how to evaluate PBO nets,and considering the manufacturer’s product claim,Olyset®Plus was evaluated as a pyrethroid LLIN.Methods:This was a household randomized controlled trial in a malaria endemic rice cultivation zone of Kirinyaga County,Kenya between 2014 and 2017.Cone bioassays and tunnel tests were done against Anopheles gambiae Kisumu.The chemical content,fabric integrity and LLIN survivorship were monitored.Comparisons between nets were tested for signifcance using the Chi-square test.Exact binomial distribution with 95%confdence intervals(95%CI)was used for percentages.The WHO efcacy criteria used were≥95%knockdown and/or≥80%mortality rate in cone bioassays and≥80%mortality and/or≥90%blood-feeding inhibition in tunnel tests.Results:At 36 months,Olyset®Plus lost 52%permethrin and 87%PBO content;Olyset®Net lost 24%permethrin.Over 80%of Olyset®Plus and Olyset®Net passed the WHO efcacy criteria for LLINs up to 18 and 12 months,respec‑tively.At month 36,91.2%Olyset®Plus and 86.4%Olyset®Net survived,while 72%and 63%developed at least one hole.The proportionate Hole Index(pHI)values representing nets in good,serviceable and torn condition were 49.6%,27.1%and 23.2%,respectively for Olyset®Plus,and 44.9%,32.8%and 22.2%,respectively for Olyset®Net but were not signifcantly diferent.Conclusions:Olyset®Plus retained efcacy above or close to the WHO efcacy criteria for about 2 years than Olyset®Net(1–1.5 years).Both nets did not meet the 3-year WHO efcacy criteria,and showed little attrition,comparable physical durability and survivorship,with 50%of Olyset®Plus having good and serviceable condition after 3 years.Better community education on appropriate u
文摘Inorganic fertilizer NPK (nitrogen, phosphorus and potassium) (S) 25:5:5:5 is generally recommended for optimum yield and quality of tea (Camellia sinensis). Non-judicious use of this inorganic fertilizer however acidifies the soils and pollutes the environment. Integrated soil fertility management (ISFM) which involves the combined use of organic and inorganic fertilizer is recommended for improved crop yield and soil health. An experiment was carried out to determine the effect of enriching cattle manure with different ratios of inorganic fertilizers (OM: NPKS at ratios 1:2 and 1:4), and rates on soil nutrient status, nitrogen uptake and yield of tea in the east of Rift Valley, Kenya. Enriching manures and organic manure up to a rate of 150 kg N/ha increased the level of P mature leaf. A higher N and K level in the mature leaf was observed when NPKS was applied at higher rates. In the soil, fertilizer rate up to 150 kg N/ha showed higher pH and K where organic manure and enriched manures were applied while NPKS treatment showed higher P content throughout the soil depths. Enriching organic manures with inorganic fertilizers increased yield significantly.
文摘The paper analyzes the relationship between remittances and financial development using Kenyan quarterly data from 2006 to 2016.Five different indicators of financial development are used:credit to the private sector as a share of GDP,the number of mobile transactions,the value of these mobile transactions,the number of mobile agents,and the number of bank accounts.The results from using an autoregressive distributed lag demonstrate a strong,positive relationship between remittances and financial development in long-run equations.This suggests that higher levels of remittances provide opportunities for recipients to open bank accounts,enhance their savings,and access financial systems,in addition to exposing the previously unbanked to both new and existing financial products.The results also confirm the potential advantage of embracing modern and advanced technology to facilitate international mobile transfers.Using international remittance transfers through mobile technology reduces costs by eliminating the need for physical branches and personnel to attend to walk-in customers.Aside from offering convenience and safety for remittance actors,this method also dominates traditional remittance business models.Therefore,a policy window exists for the government to leverage on remittances as a tool of financial inclusion and depth,and particularly through the continued expansion of regulatory space to accommodate the wider use of international mobile remittance transfer channels.Moreover,given the strong,positive relationship between remittances and credit to the private sector as indicated by its share of GDP and number of bank accounts,commercial banks and other players in the remittance market may also find it useful to develop customized products for migrants to access their remittances.For example,financial intermediaries can consider providing better deposit interest rates for diaspora deposits compared to deposits made in the local currency.Further,these institutions can allow regular remittance flows to act a
文摘Busia and Kisii Central districts are areas in western Kenya that have repeatedly reported high levels of stunting growth in children and an increase in hepatocellular carcinoma (HCC);an aspect often positively associated with chronic exposure to aflatoxins especially through consumption of foods such as peanuts. The objectives of the study were to determine the incidence, types and levels of aflatoxin in different varieties of peanuts produced in Busia and Kisii Central districts. One hundred and two (102) peanuts samples were collected from farmers’ in each district. Aflatoxin types and levels of aflatoxins were analyzed using high performance liquid chromatography (HPLC) technique. All the peanuts samples from Kisii Central and 97.06% samples from Busia were contaminated with aflatoxins. However, aflatoxin was not detected in 2.94% of samples from Busia district. The levels of total aflatoxin ranges were 0.1 to 268 μg/kg and 1.63 to 591.1 μg/kg in peanuts from Busia and Kisii Central respectively. Majority of peanuts samples had levels within Kenya Bureau of Standards (KEBS) and European Union (EU) regulatory limits for total aflatoxins. Improved variety (Valencia red) had significantly lower aflatoxin contamination compared to local varieties (Uganda local red, Homabay local and Local red). Aflatoxins B1, B2, G1 and G2 were found in peanuts;B1 was the most predominant in both districts (t = 12.4, df = 3, P = 0.034). The levels of aflatoxins especially in peanuts from Kisii Central district were high (591.1 μg/kg) where 44.6% of samples analyzed were unfit for even animal feed (USFDA regulatory limit). An assessment on the levels of aflatoxins should be done by the relevant stakeholders in other key foods in the areas for example maize. The most lethal aflatoxin type B1 was found to be the most predominant peanuts from both districts of study. This calls for frequent aflatoxin screening of peanuts from the districts particularly aflatoxin type B.